Chinese Herb Chang Shan Targets Autoimmune Disorders

For roughly two thousand years, Chinese herbalists have treated Malaria using a root extract, commonly known as Chang Shan, from a type of hydrangea that grows in Tibet and Nepal. More recent studies suggest that halofuginone, a compound derived from this extract's bioactive ingredient, could be used to treat many autoimmune disorders as well. Now, researchers from the Harvard School of Dental Medicine have discovered the molecular secrets behind this herbal extract's power.

"Halofuginone prevents the autoimmune response without dampening immunity altogether," researcher Malcolm Whitman, PhD, professor of developmental biology at Harvard School of Dental Medicine, says in a news release.

"This study is an exciting example of how solving the molecular mechanism of traditional herbal medicine can lead both to new insights into physiological regulation and to novel approaches to the treatment of disease," researcher Tracy Keller, an instructor in Whitman's lab, says in the release.

Cells stop the synthesis of non-vital proteins when amino acids are in short supply. Keller's team discovered that halofuginone mimics such a shortage by blocking an enzyme that feeds one amino acid to the protein-making machinery.

Keller found that the drug triggers a chemical cascade that responds to amino acid scarcity, called AAR. This inhibits the growth of malaria parasites, stops blood cells from making proteins that cause inflammation, and stops the development of specific white blood cells that trigger conditions such as inflammatory bowel disease and multiple sclerosis.

This could make the drug effective against autoimmune disease. But as halofuginone mimics nutrient deprivation, there is another possible use. Animals that receive only just adequate nutrition are known to live longer, partly because diseases which involve inflammation are prevented. That, says Keller, means halofuginone might possibly work as an anti-aging drug.